大螟两个mGST1基因的时空分布及经氯虫苯甲酰胺诱导后的表达情况

Temporal and spatial expression profiles of two mGST1 genes in Asiatic pink stem borer Sesamia inferens and their expression induced by chlorantraniliprole

为明确微粒体谷胱甘肽S-转移酶(microsomal glutathione S-transferase,mGST)是否参与大螟Sesamia inferens对氯虫苯甲酰胺的解毒代谢,采用Illumina深度测序技术分析大螟转录组数据获得mGST1基因序列,利用实时荧光定量PCR技术测定其在大螟不同龄期幼虫和4龄幼虫不同组织中的表达模式,及经不同浓度氯虫苯甲酰胺处理不同时间后的相对表达量。结果表明,共获得2个mGST1基因序列,分别命名为SimGST1-1和SimGST1-2(GenBank登录号分别为OL770267和OL770268)。SimGST1-1和SimGST1-2的开放阅读框分别为456 bp和447 bp,分别编码152个和149个氨基酸,均具有昆虫mGST的特征序列。SimGST1-1和SimGST1-2在大螟不同龄期幼虫体内均有表达,且在4~6龄幼虫体内的相对表达量显著高于1~3龄幼虫。SimGST1-1在4龄幼虫中肠和脂肪体中的相对表达量显著高于在头部和表皮中的相对表达量,SimGST1-2在头部和中肠中的相对表达量显著高于在表皮和脂肪体中的相对表达量。与对照组相比,50、100、200、400 mg/L氯虫苯甲酰胺处理大螟4龄幼虫后对SimGST1-1和SimGST1-2的表达均有显著诱导作用,且呈现明显的剂量效应;利用400 mg/L氯虫苯甲酰胺处理4龄幼虫后,随着处理时间延长,SimGST1-1和SimGST1-2的表达也呈现较明显的时间效应。表明SimGST1-1和SimGST1-2基因可能参与了大螟对氯虫苯甲酰胺的解毒代谢过程。

In order to clarify whether microsomal glutathione S-transferase(mGST)are involved in the detoxification and metabolism of chlorantraniliprole in Asiatic pink stem borer Sesamia inferens,mGST1 gene sequences were obtained from the transcriptome data of S.inferens based on the Illumina deep-sequencing,and the expression patterns of mGST1 genes in different instar larvae and different tis-sues of the 4th instar larvae of S.inferens,and their expression levels in the 4th instar larvae treated with different concentrations of chlorantraniliprole for different durations were determined by qPCR.The results showed that two mGST1 genes,SimGST1-1(GenBank accession no.OL770267)and SimGST1-2(GenBank accession no.OL770268),were obtained.The open reading frames of SimGST1-1 and SimGST1-2 were 456 bp and 447 bp in length and encoded 152 and 149 amino acids,respectively.SimGST1-1 and SimGST1-2 were expressed in different instar larvae,and their relative expression lev-els in 4th-6th instar larvae were significantly higher than in 1st-3rd instar larvae.The relative expres-sion levels of SimGST1-1 in the midgut and fat body of 4th instar larvae were significantly higher than in the head and epidermis,and SimGST1-2 showed significantly higher relative expression level in the head and midgut than in the epidermis and fat body.Compared with the control group,treatment of the 4th instar larvae of S.inferens with 50,100,200,400 mg/L chlorantraniliprole exhibited a significant dose-dependent induction effect on the expression of SimGST1-1 and SimGST1-2.When the 4th instar larvae were treated with 400 mg/L chlorantraniliprole,the expression levels of SimGST1-1 and SimGST1-2 increased with increasing durations after treatment,suggesting an obvious time effect.These results indicated that SimGST1-1 and SimGST1-2 genes were probably involved in the detoxifica-tion and metabolism of chlorantraniliprole in S.inferens.